🔍 Key Concepts

• Narrow channel shiphandling – how large vessels actually pass each other in confined waters • Effects of bank cushion and bank suction vs. squat in shallow water • Where a pilot prefers to keep the ship (mid‑channel vs. near the bank) before making a meeting maneuver

💭 Think About

• In a narrow channel, what hydrodynamic effects act on a ship that gets too close to the bank, and how do they influence course-keeping and safety when another vessel is approaching? • Is the pilot more worried about underwater clearance directly beneath the keel, or about interaction forces between the hull and the channel bank when passing another ship? • Of the four choices, which one most directly explains why the pilot is deliberately delaying the move to starboard rather than describing a general advantage of being in mid‑channel?

✅ Before You Answer

• Compare bank cushion / bank suction with squat: which is mainly about sideways forces near the bank, and which is mainly about vertical sinkage due to speed in shallow water? • Ask yourself: just before two ships meet in a narrow channel, which side‑force effect becomes critical if one vessel moves too close to the bank? • Eliminate any options that could be true in many situations but do not specifically explain the timing of the pilot’s course change in this meeting situation.